accelerator

American  

[ak-sel-uh-rey-ter] / ækˈsɛl əˌreɪ tər /

noun

accelerators plural

1. a person or thing that accelerates.

2. Automotive. a device, usually operated by the foot, for controlling the speed of an engine.

3. British. any two- or three-wheeled motor vehicle, as a motorcycle or motor scooter.

4. Photography. a chemical, usually an alkali, added to a developer to increase the rate of development.

5. Also called accelerant.  Chemistry. any substance that increases the speed of a chemical change, as one that increases the rate of vulcanization of rubber or that hastens the setting of concrete, mortar, plaster, or the like.

6. Anatomy, Physiology. any muscle, nerve, or activating substance that quickens a movement.

7. Also called particle accelerator.  Also called atom smasher.  Physics. an electrostatic or electromagnetic device, as a cyclotron, that produces high-energy particles and focuses them on a target.

8. Economics. acceleration coefficient.

9. Business. an enterprise that provides investment funding and short, fixed-duration mentoring and education programs to a select group of startups that apply for this, including access to networking, strategy coaching, collaborative workspace, etc.

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accelerator British  

/ ækˈsɛləˌreɪtə /

noun

1. a device for increasing speed, esp a pedal for controlling the fuel intake in a motor vehicle; throttle

2. Also called (not in technical usage): atom smasher.  physics a machine for increasing the kinetic energy of subatomic particles or atomic nuclei and focusing them on a target

3. chem a substance that increases the speed of a chemical reaction, esp one that increases the rate of vulcanization of rubber, the rate of development in photography, the rate of setting of synthetic resins, or the rate of setting of concrete; catalyst

4. economics (in an economy) the relationship between the rate of change in output or sales and the consequent change in the level of investment

5. anatomy a muscle or nerve that increases the rate of a function

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Other Word Forms

Noun Inflected Forms

• accelerators
  plural

Etymology

Origin of accelerator

First recorded in 1605–15 and in 1930–35 accelerator for def. 7; accelerate + -or ²

Explanation

An accelerator makes things go, or accelerate. The gas pedal on a car is an accelerator, but so is a machine that scientists use to speed particles up and smash them. An accelerator gets things going. In a car, the accelerator is the gas pedal that you mash with your foot when you’re ready to speed off into the sunset. In physics, a particle accelerator speeds off in a different way — it takes a particle, such as an electron, and speeds it up to almost the speed of light, and smashes it into an atom. Why? To see what it’s made of.

Example Sentences

The new AI accelerator is optimized to meet the demands of current and future AI models, OpenAI said, adding that engineering samples are now running machine learning workloads, including its GPT-5.3-Codex-Spark text-only coding model.

From MarketWatch • Jun. 24, 2026

“I have always known that there is no greater accelerator of change and opportunity than the school house, and that is still true today,” Chait added.

From Los Angeles Times • Jun. 24, 2026

He also claimed that the driver "had the accelerator pushed even after the crash".

From BBC • Jun. 24, 2026

Tesla’s vice president of AI and software, Ashok Elluswamy, claimed the driver manually pressed the car’s accelerator pedal down, in a post shared to social-media platform X.

From Barron's • Jun. 23, 2026

I took my foot from the accelerator and lightly pressed on the brakes.

From "Breaking Through" by Francisco Jiménez

Related Words

• particle accelerator